How To Install An Engine Oil Cooler Kit

Have you ever popped the hood after a spirited highway pull or a weekend canyon run and thought, “Wow… my oil temps are cooking!”? If you have, you already know why an engine oil cooler kit matters. High oil temperatures thin your lubrication, accelerate wear, and rob performance. Installing an oil cooler kit is like giving your engine a much-needed breathing room — and trust me, once you do it, you’ll wonder why you didn’t earlier.

I remember my first oil cooler install — an old turbo four-banger that loved boost but hated heat. Watching the temps drop after installation felt like conquering a boss level in a video game. If you’re reading this, chances are you want the same win — lower temps, better reliability, and the satisfaction of DIY.

So let’s tackle it together, step by step, like two buddies wrenching in the driveway.

Why Install an Engine Oil Cooler?

Before diving under the car, let’s get on the same page. Oil coolers do one job extremely well: reduce oil temperature — especially under load, towing, track use, or even daily driving in a hot climate.

Here’s what they give you:

• Improved lubrication stability
• Reduced wear on bearings and internal components
• Better resistance to oil breakdown
• Higher performance tolerance before overheating

Think of it like giving your engine its own radiator system — because that’s basically what it is.

What You Need Before Starting

Planning makes or breaks this job. A poorly prepped install = leaks, routing issues, or worse, running out of parts halfway through.

Here’s your basic kit checklist:

• Engine oil cooler core (plate or tube/fin style)
• Oil sandwich adapter or remote filter mount
• AN lines (most common sizes: AN-8 or AN-10)
• Fittings (90°, 45°, or straight depending on routing)
• Hose clamps or AN collars
• Mounting brackets
• Oil, funnel, and drain pan
• Torque wrench
• Ratchets, pliers, sockets, drill (if fabricating mounts)

Pro tip? Always inspect your kit — missing fittings are more common than you think.

Choosing Where to Mount The Cooler

Location makes all the difference. Airflow is your friend — block it, and your cooler becomes useless.

Best placement options include:

• In front of the radiator or AC condenser
• Behind a grill opening
• Inside bumper ducting
• Side-mount airflow channels in performance cars

Ask yourself:

Does this area get airflow when I’m driving, not just when idling?

That question alone will guide you well.

Step-By-Step Install: Let’s Get Our Hands Dirty

Alright — enough talking. Time to wrench.

Step 1: Elevate the Vehicle

Grab jack stands. A lift makes life easier, but stands work fine.

• Ensure the surface is level.
• Use jack points recommended by your car manufacturer.
• Give the car a nudge (safely!) to ensure it’s stable.

A shaky setup is how projects become stories your mechanic laughs about — don’t be that story.

Step 2: Drain the Engine Oil

Warm the engine for a few minutes first — warm oil drains faster.

• Position drain pan
• Remove oil drain plug
• Let it fully drain

Now is also a great time to swap oil weight if you’ve upgraded cooling — thicker oil + cooler = happy engine.

Step 3: Install the Oil Sandwich Adapter

This is where the magic begins.

Remove the old filter and thread on the sandwich plate. Most kits include two O-rings — one for the plate face and one sealing the sender ports.

Make sure:

• The ports face in a direction that won’t interfere with exhaust or engine mounts.
• The plate is hand-tightened first, then torqued.

Over-tightening = leaks. Under-tightening = leaks. Find the sweet spot.

Step 4: Mount the Cooler Core

Position your cooler so airflow meets the front face, not the back of the fins.

Mounting options include:

✔ Brackets
✔ Zip-through radiator straps
✔ Bolt-on hardware

Whichever method you use, ensure:

• The cooler sits rigid — no vibration buzzing.
• It isn’t touching the radiator directly (heat soak).

Do you need ducting? For hard track use — yes. For street and light loads — not always.

Step 5: Route The Oil Lines

This part makes most beginners nervous — don’t worry, we’ll break it down.

Follow these rules:

• Never run the lines next to exhaust headers — heat kills oil pressure.
• Avoid tight bends — AN lines don’t like choking.
• Secure away from sharp edges — abrasion = leaks.

Routing tips:

• Test-fit before tightening connections.
• Use P-clamps or zip ties to secure.
• Aim for gentle curves, not 90° kinks.

Which port goes where?

Generally:

• OUT port on sandwich → cooler IN port
• Cooler OUT → sandwich return port

Some kits label flow direction, but many don’t — always check instructions.

Step 6: Tighten and Secure All Fittings

Oil cooler installs fail here more than anywhere else.

Check each fitting:

• Is the collar properly seated?
• Are AN hoses fully inserted?
• Is every clamp torqued?

Double-check — then check again. Your garage floor will thank you.

Step 7: Fill Oil & Prime The System

This step is HUGE.

Your cooler and lines add extra oil volume — usually 0.5 to 1 full quart.

Steps:

1. Reinstall drain plug.
2. Fill engine with recommended oil, and then add a little extra for cooler capacity.
3. Before starting, crack a fitting to let air escape (optional).
4. Start engine for 5–10 seconds, shut off.
5. Recheck oil level — top up.

This primes the cooler and avoids running dry.

Step 8: Fire Up & Check For Leaks

Start the engine and watch:

• Fittings
• Sandwich plate
• Cooler ends
• Oil filter area

Don’t panic if a little drip appears — tighten fittings gradually.

Let the engine idle until warm, then rev gently and look again.

If you see foamy oil, the lines are cavitating — shut down and re-prime.

Step 9: Test Drive & Monitor Temps

Your first drive is the moment of truth.

Watch:

✔ Oil pressure
✔ Oil temperature gauge (if installed)

You should see temps stabilize earlier and recover faster after hard throttle.

If temps don’t drop, airflow or routing may need improvement.

Plate vs Tube Oil Coolers — Which Is Better?

If you’re curious (and you should be), plate coolers are more efficient — better for performance cars. Tube/fin coolers are budget-friendly and decent for towing.

Quick breakdown:

Plate Coolers

• Higher heat transfer
• More compact
• Best for turbo/track builds

Tube/FIn Coolers

• Cheaper
• Larger footprint
• Good for moderate heat loads

Pick based on how hard you drive — not just cost.

Common Mistakes To Avoid

You’d be surprised how many enthusiasts do these:

❌ Forgetting to add oil for cooler volume
❌ Running lines near exhaust
❌ Using cheap hose clamps on high-pressure systems
❌ Mounting cooler behind a bumper with no airflow

Here’s a simple list to stay ahead:

• Use AN fittings when possible
• Route away from heat
• Always secure hoses
• Double-check torque values

These small details make your install bulletproof.

Do You Need a Thermostat?

Some kits include thermostatic sandwich plates — IMO, they’re worth it.

Why?

Because cold oil is just as bad as hot oil.

Thermostats:

• Keep temps in the sweet spot.
• Reduce cold-start wear.
• Prevent oil over-cooling on highway cruising.

If your climate swings hot to cold or your car sees street use — grab one.

How Long Does Installation Take?

On average:

• Beginner mechanic: 3–4 hours
• Intermediate DIY: 1.5–2 hours
• Pro shop: under 1 hour

Expect more time if you’re making custom brackets or relocating filters.

Maintenance After Installing The Cooler

Oil cooler systems aren’t “install and forget.” Quick weekly checks (at first) are smart:

• Look for sweating fittings
• Inspect for line abrasion
• Watch pressure/temperature readings

At each oil change:

✔ Flush cooler if needed
✔ Inspect hoses for stiffness or cracking

Once dialed in, they’re incredibly reliable.

Final Thoughts: Enjoy The Satisfaction

There’s nothing like hearing your turbo spool, seeing oil temps stay cool, and knowing you made it happen.

Installing an engine oil cooler kit isn’t just about temps — it’s about confidence. It’s the kind of upgrade that feels technical, but once you’ve walked through it step-by-step, you realize it’s totally doable.

So if you’ve been on the fence, here’s my nudge:

Grab your wrenches, queue up some music, and give your engine the cooling upgrade it deserves. You’ll learn, you’ll enjoy it, and your ride will thank you every time you hit the throttle.

Now get out there, build something awesome, and keep those oil temps happy 😄